Vase printig mode seems really wrong

[widden 2]

Hey everyone.  I need a bit of help with a weird thing here in vase mode.  Might be a bug, dunno.

I've created a post on reddit, but it seems no-one has a clue what maybe causing this, so I thought I try my luck here.

 

Here's a video to the issue posted on reddit: https://www.reddit.com/r/ender6/comments/r3zxn3/vase_mode_printing_in_small_slow_steps/

 

A description of the issue is as follows;

The initial layers print at full speed, then the whole thing changes to this. In cura, the print shows up to complete in an hour. But at this speed it'd take all night. In normal mode this model should be ~4.5hrs.

 

Printer: ender-6 (using it via SD card, no direct USB connection)

Special settings that maybe relevant:

Spiralize Outer Contour : on

Minimum layer time: 2 s

Minimum speed: 20 mm/s

Layer height: 0.2 (initial the same)

Line width: 0.4

 

And speeds are of course all set way higher - even the initial layer is at 20 mm/s the rest are 60-80
I've started this print 3-4 times, tried small tweaks, but to no avail.

 

Here's the gcode file, in case it helps - of you want to test it. https://www.dropbox.com/s/wucwy9xfgkx47f4/SpiralOrnament.profile.26.gcode?dl=0

Trying to print this model: https://www.thingiverse.com/thing:4678220

Thanks for any help!

Edited November 29, 2021 by widden

[tinkergnome 927]

Feedrates in the gcode file are matching your description.

But it seems like the model has a very high resolution - and your printer can't handle so many instructions per second.

 

Take a look at "Maximum Resolution" / "Maximum Deviation" in Cura (increasing these values will decrease the file size).

 

 

[GregValiant 1,251]

I responded to your post on reddit as well.  It's as Tinkergnome said.  The high resolution is causing stuttering.  The 2500 Accel setting and the 80mm/sec print speed is causing issues as well as the printer is struggling to read all the gcode and the buffer is running dry causing the printer to have to wait for another instruction to show up.

 

I started to print your gcode file and made it about 150 layers before aborting it.  It did not look good as there were a lot of surface defects.  The one on the left is my slice at 75mm/sec and 500 Accel 8 Jerk.  Print time was 1:45.  The yellow circles are surface defects from the nozzle hesitating.  I cut the feedrate to 70% (at about the red line) and it finished really well.  (I cut it off in the image but the point printed quite well too.)

 

 

Here the gold one is at 35mm/sec, Maximum Resolution at 0.5, and I cut the temperature down to 200 at layer 435 to help the top, but really, the blue one came out pretty good at 210 all the way up.  (I had to print it in gold because the wife walked by while I was printing the blue one.  "That won't match"..."What color would you like dear?")

 

Edited November 29, 2021 by GregValiant

[widden 2]

Thanks gents for all the responses, I'll try to digest it and make modifications.

I'd just like to say I really appreciate you both taking the time and effort and help me here.

I forgot to mention that I've been into 3D printing for a whole of 2 weeks at this point, so a lot of things are still 'alien'.  

For one thing the profile I'm using as a base is someone else's creation to combat stringing (which it does), which maybe messing with the vase mode.

 

Edit: love that wife comment with the gold 🙂  Yeah it does happen here already, too.

Edited November 30, 2021 by widden

[widden 2]

Well, I've now tried to go back to a 'standard' profile for starters. 

Then going up to

max resolution=1mm
max deviation=0.2mm

And it's still the same.  Larger hops, but no material difference.  Takes half a minute to do one revolution around the model.
I think I'll just put it down to Ender 6 not able to print in this mode, and leave it at that - for now.

Many thanks again, gents!

[GregValiant 1,251]

At the top of the Cura settings area is the Settings Search box.  Just to the right of that is an icon with 3 lines on it.  It's the Settings Visibility tool.  Click on it and select "All".

Every model has it's own requirements.  Some require support, maybe tree support is better for that model.  Some are basic rectangles and can be printed at 80mm/sec at high Accel and Jerk.  Models with a lot of curves print better at slower speeds and lower Accel and Jerk.  For every different model, I go through ALL the settings to customize Cura for the particular model.  Attention to detail before you start squirting plastic makes for a much smoother experience and a lot less scrap.

 

A lot of people like to bling their printers with different sorts of plastic parts (I'm one of them).  99% of those parts are solutions to problems that don't really exist, but you are slicing, printing, and gaining experience along the way.  I don't consider any printed part to be art (the art is in the model design and the post-processing), but I think slicing a model could be considered an art.  There is a lot to think about to get it right, and how a person decides to set up the slice can make a huge difference in the quality of the print.

 

Here is the air inlet for my power supply fan.  I mean really...was this necessary?  I learned quite a bit about support (and how to remove it) from this dumb thing so it had value to me, but really....

Edited November 30, 2021 by GregValiant

[geert_2 557]

When you are new into 3D-printing, I would suggest that you print a small testmodel, that does not cost much time and material, at various settings:

- temperature: start from recommended setting, then also print it in steps of 5°C lower and higher, until it gets deformed (underextrusion when cold, or way too liquid when hot). But do not go too hot, so the material does not decompose and gets brown or gets stuck in the nozzle.

- speed: idem, start from recommended, then change in steps of 10mm/s up and down. See the effect on accuracy and under-/over-extrusion.

- try various layer heights: thin layers give smoother surfaces, but thick layers give better overhangs (on my printers).

- design a model with various angles of overhangs, and see how they print.

- design a model with tiny holes, and see how they shrink and print.

- try the various options and settings, and see what effect they have.

- try various bonding methods.

- try changing speed and temp on the fly, if your printer allows it: then you can quickly see the effect.

 

So, design a small test model with some holes, some 90° angles (to examine effects like overshooting and ringing at corners), some smooth radiusses, various overhangs, bridges, etc.

 

When printing fast, increase temp a bit, since the nozzle has to melt more plastic in the same time. When printing slow, decrease temp, so the material does not decompose due to sitting too long in the nozzle. Generally, printing at the cooler and slower edges of the range, improves the results. But it takes more time...

 

Keep watching the printer closely: how it extrudes, how it moves, how it pulls along the extruded sausage, what defects if any, how the nozzle leaks, how it creates strings, etc... Just watching this will give a lot of understanding.

 

[widden 2]

Thanks guys, I'll take it to heart.

 

I've already done a few test prints already; eg I've done a temp tower, (which showed no difference from 195-225 to me), done overhangs - which was good to see that I can print well up to ~70 degree overhangs.

 

I've also fought a fuckload with first-layer adhesion (pardon my french).  I've now tried pretty much everything apart from installing a G10 sheet (which has arrived, I just need to cut it to size, and it's toxic when cut).

 

To be honest I'm a bit over it.  I'd like to just design and print stuff, but I can already see it won't work without learning all the nuances, however for that I need to print a lot more than tests (eg I've learned more about supports trying to repeatedly print a wolf miniature for my daughter than trying tests)

 

At the same time using too small models always causes problems; easy breakage and invisible details (my eyesight isn't what it used to be).

Anyway, looks like a long journey ahead.  Just not too happy with this ender-6 right now.

Edited December 1, 2021 by widden

[GregValiant 1,251]

 "...Just not too happy with this ender-6 right now."

 

My Ender 3 Pro is 2 years old now.  It is much better now than when it was new.  Mostly because all the weaknesses have showed up and been addressed.  New fans, all metal hot end, it's on it's 3rd mainboard, glass build surface, aluminum extruder, 5015 cooling fan, and the operator now has some idea of what he's doing.

That last item is the most important part.  The learning curve on these can be steep.  Cura is not simple software to get to know.  At least a rudimentary knowledge of Gcode is required.  If you want to design you own things there is another piece of complicated software involved.

The first thing though...do not assume that anything on the machine was assembled correctly.  Get out your carpenters tri-square and a straight edge and go over the frame and make sure that the three axes are perpendicular to each other.  Check that all the wheels provide good contact with the beams so nothing shakes, rattles or wobbles and the belts are tight.  Check all the screws for tightness and that includes the hot end mount.

I know these are cheap machines (that's why I bought one) but all the parts are there and they fit together (more or less).  Your first job is to tune the frame, belts, running gear, etc. to give it a good shot at making quality prints.  Mine runs well on large rectangular models and PLA up to about 125mm/sec at Accel 2000 and Jerk 20.  On circular models - above 60mm/sec starts causing herky-jerky movement even with the Accel at 500.  I started a 14 hour rectangular print 3 hours ago with PETG which I print at 35mm/sec with the Accel and Jerk at 2000 and 20.  It isn't fast, but on my printer PETG goes down very well and with good accuracy at that speed.  I recall that you had your speed set to 80 for that ornament.  If you want to run hard like that you really need to know how to tune a slice, and the machine needs to be well tuned.  After a while you will recognize what to do with a particular model.

 

Here is an app I wrote to talk to the printer.  It's kind of like Pronterface but it does not send a gcode file to the printer.  Instead, it controls printing from the SD card by sending gcode commands to the printer.  It doesn't have a digital signature (which I would have to pay for) so if you install it you would probably need to explain to your anti-virus why you think it's OK.

 

I humbly call it Greg's Toolbox.  The reason I'm passing it along is so you will have ANOTHER piece of software to learn.

[widden 2]

Haha, you're my kinda guy, Greg.

Funnily, building stuff is the bit I enjoy a bit more, I've already designed a few simple things in SCAD.

 

Thanks again!  I'll persevere.
And I'll check out your software.
 

Edited December 1, 2021 by widden

[widden 2]

Gents I've managed to print this model, simply with 'normal' settings for now.
 

It's not bad for a first try I guess, but there's some weird blemish (that's repeated all the way around at the same height)  as it can be seen here:


May I ask you more experienced printers, what could cause this and what maybe a good idea to try to fix it?
I know we're outside of talking about Cura now, however, I'm quite unsure what to touch, what maybe the potential cause.
(I've attached the gcode in case it helps)

Basically I've taken a decent profile - not too fast I hope, this time, it took 3.5hrs - and made it into a single-wall, no-infill one.
Speed at 60, accel at 2000, jerk at 8.
 

SpiralOrnament.profile.32.gcode

[GregValiant 1,251]

@geert_2 might have a take on that.  It appears to have happened during the widest area and that would have been the fastest area too.  What temperature did you print at?  

 

I just re-read your post.  In vase mode that file took 1hr 45min for me to print.  Post the gcode file you printed please.  I'll take a look at that.

 

This is the file I sliced and printed.  It should print on your machine if you want to give it a shot.  The first 20 or 25 layers should give you an idea on how it's running.

GV_Ornament.gcode

Edited December 2, 2021 by GregValiant
Added comment and file

[widden 2]

Thanks, @GregValiant I'll give it a try! 

 

And you're right it is on the widest part so yeah, it may still be speed...

 

Btw my gcode was/is attached to the post 🙂

 

Edit: I've given your gcode a try, and the printer went into the original skippy/staggery mode again - it's probably using the 'vase' mode, which mine simply cannot do it seems. 
 

 

Edited December 2, 2021 by widden

[GregValiant 1,251]

Got it.

When you print it with a conventional single wall you tell Cura the wall thickness.  Cura calculates the wall thickness by a dimension that is perpendicular to the surface of the wall.  It will then call for more plastic to maintain that wall thickness.  In the case of the ornament - around layer 28 Cura starts adding movements to extrude material where the wall needs to be thicker.  Cura defines those movements as "skin" rather than "inner-walls" but the effect is the same as a wall.

Those movements max out at about layer 260 (where it is printing at a full 60mm/sec) and then disappear as the walls get near vertical.  That's normal behavior but increases the print time from my spiral slice at 6303 seconds (1:45) to your normal slice at 13729 seconds (3:45).

 

That might be what you are seeing in your print.  There is more material where you see that pattern in the finished print and the gold is slightly translucent.

 

The 3mf file below has been sliced in Normal fashion with a single wall, no top and no bottom, with a support blocker configured as an "infill mesh" with the Bottom Layers set to 4.  You will see that the print time is down to 1:45 and that the entire model has a single thickness all the way up.

GV_Ornament_thin_normal.3mf

[widden 2]

Mate, your project/config is working brilliantly - and it has finished, indeed, in 1:43 !

The only thing I had to change was the z-hop speed; it came up red at 20; I had to reduce it  to 10


 

There's only one small, barely visible blemish on one side, weirdly in a near-vertical direction this time rather than horizontally:

 

My question, regarding cura this time (hurray!)
is there any way to see how your profile differs from mine?

A setting-by-setting comparison view of some sorts would be great.

 

I need to know how exactly to achieve such a great result 🙂

 

Thanks for all the help, again!

Edited December 3, 2021 by widden

[GregValiant 1,251]

The flaw may have been a random blob that came off the nozzle.  No way to tell really.  The way the print ran for the rest of it I'm guessing it had to be something like that because 99.99% of it looks really good.

 

I think there is a way to export settings but it's something I've never used.  In the Marketplace there is a plugin called "Export HTML Cura Settings".  You will have to play with it.  Maybe @gr5 or @tinkergnome can help with that.

 

Out of curiosity - how are you feeling about that Ender 6 today?

[widden 2]

I've found out how to compare profiles from this page on github, and this is the result:
https://www.diffchecker.com/1q3CCLfs

A bit too many to digest easily, that's for sure.

About that slight blemish; it's happening near-vertically on the edges repeatedly - so I'm thinking maybe it's the z-seam that is not-that-well hidden? 

I'm still a bit miffed at the Ender-6, due to a number of small nagging issues to be absolutely honest. 
Some due to the loose spec chinese manufacturing and lack of proper QC, I reckon.  But it'll do as a learning printer.  I'm already eyeing a Voron with a 350 bed, hehe...except I'd rather have someone else put it together.  And I need to get that new shed installed, which will take a few months (The family isn't enjoying the noise; although my daughter enjoys the prints.  The latest articulated gecko was a real hit 😁 ) .

One issue for example; I've bought new wheels to deal with the strong dusting, and it turns out it's still dusting. It's because things don't align perfectly; kind of like you said before.   But I've no idea what to do with it; the whole y-axis carriage on the right seems slightly out of alignment for one.   To fix it it'd probably need a new rail cut to size and drilled and...and...bugger it.
This is the picture demonstrating the issue:
https://ibb.co/HnzzssX
But there's some dusting from the wheels on all the other rails, too; just not this uneven.
 

[GregValiant 1,251]

I've never been up close to one but with my E3Pro shimming is pretty easy.  The Z motor was holding the Z rod out of alignment.  It required .024" of shim to get it to line up.  The Y beam (assembled by the factory) was angled to both the X and Z.  That just required some screws to be loosened and the adjustments made.

Your frame is much more elaborate but you are getting a handle on where the issues are.  Pieces of paper can be used as shims.

The Chinese have talked about going to the moon.  Unless they have someone else build the equipment I don't see them making it.  Their QC seems to be defined in two words..."close enough".

[widden 2]

Hah, heard the story that Armstrong has fixed the Apollo 11 during their moon mission with a ball pen?

 

It's possible to get there in nearly anything, but needs a bit of luck 🙂

[GregValiant 1,251]

So NASA needed to come up with a pen that would write in zero G so the astronauts could keep notes.  They spent $5 million dollars and solved the issue by placing a small pump inside the pens.

 

The Russians used pencils.

Edited December 3, 2021 by GregValiant

[fergazz 60]

Hi @widden, welcome to the club!

 

in “vase mode” you have a continuous extrusion so the printer do not retract… it is also called “spiralize mode”. So you doesn’t have problems with z-seam because it happens when the printhead moves from one place to the other (or to another layer) and needs to retract.

 

Regarding the “strong dust” I suppose that this should be related to the excentric nuts too tight… causing deformation on the POM wheels and leaving some residual. The excentric nut is an out of axis nut… so you need to find the sweet spot to hold but not thingt too much and not too lose… no wooble. It approuchs and leave a gap of the gantry while you turn it. You can find these nuts on the v-slots (the alone one in that triangle) and under the bed base if your bed moves in Y direction front to rear (I supose Ender 6 don’t have this kind of bed as Ender 3, for exemple). If it’s too tight it creates resistence that are showed into the surface of the prints. Take a look of the overall shape of this wheels and keep that in mind. if it’s deformed it’s easy and unexpensive to replaced and you can have a longer life of this opting for a PP wheel that is much more rigid.

 

I hope I understood what you mean with strong dust 😁… if it’s not the case let us know. 

 

Cheers! Fernando Gazzola

3dSolid_br

Edited December 10, 2021 by fergazz